We will use bioengineering, computer and endocrinological methods for a multidisciplinary study of intrauterine environmental effects on development in chronically instrumented fetal sheep. Project 1 tests the hypothesis that fetal behavioral development is significantly affected by myometrial activity. It will use for the first time continuous computer based data-acquisition systems to assess and quantify the interrelationship of fetal electrocorticogram, electrooculogram, breathing, swallowing and voluntary movements over the critical period of development 130-140 days gestation and tests the hypothesis that uterine contractility modifies fetal behavioral development. Project 2 examines development of fetal sensory behavior and learning. A series of experiments will test the hypotheses: (1) the fetus exhibits behavioral responsiveness to various forms of sensory stimulation during the last third of gestation; (2) fetal behavior will be modified following experience with a particular stimulus, including a decrement in quantitative measures of responsiveness following repeated stimulus presentation; (3) experiential changes in fetal responsiveness will not be attributable to peripheral effects e.g. receptor adaptation or effector fatigue; (4) the fetus will retain information from early experiences to affect subsequent behavior. Project 3 investigates the ontogeny, mechanism and function of cyclic motor organization (CM) in the fetal sheep. CM is a stable aspect of behavioral organization in the 3rd trimester human fetus and other species, and is likely to regulate adaptive interactions with the environment. The mechanism of CM may be a very common one, so that understanding it would have broader significance. It also provides an opportunity to test the utility of dynamical systems theory in explaining behavior. Specific aims address the effects of behavioral state and myometrial activity, the sources of CM, the mechanism's dynamics, and the role of CM in modulating responses to stimulation. Abnormalities of intrauterine brain and behavioral development have long term adverse impact on the individual, family, and society. These integrated projects will provide fundamental information on the physiology and pathophysiology of uterine environmental influences on development and assist in development of rational therapies for antenatal care and interventions.